Material Taken From: Mathematics for the international student Mathematical Studies SL Mal Coad, Glen Whiffen, John Owen, Robert Haese, Sandra Haese and Mark Bruce Haese and Haese Publications, 2004

Stem and Leaf Plot stemleaf Used for small data sets. Shows raw data. Allows for easy identification of the mode and median. The leaf must always be a one-digit number. Section 5C – Grouped Discrete Data

Back to Back Stem and Leaf Plot Useful for comparing two small sets of data.

37, 30, 17, 13, 46, 23, 40, 28, 38, 24, 23, 22, 18, 29, 16, 35, 24, 18, 24, 44, 32, 54, 31, 39, 32, 38, 41, 38, 24, 32 A local hardware store owner recorded the number of people visiting the store at lunch time. He recorded the data for 30 consecutive weekdays. Problem 1

Organize and Display the Data: Tally and Frequency Table (Groups of 10). Column Graph. Stem and Leaf Plot.

Results for hardware store data:

Pg Consider the weights of students in a rugby training squad. Weight Interval Frequency 50  w <  w <  w <  w <  w < Section 5D – Continuous Data

Each group is called a class. The size of the grouping is called the class interval. The class interval must be the same throughout the table. It is generally a good idea to have 5 to 10 classes. Weight Interval Frequency 50  w <  w <  w <  w <  w < 100 3

Histogram

Side-by-Side View Weight Interval Frequency 50  w <  w <  w <  w <  w < 100 3

For continuous data, the Column Graph is called a Histogram and the bars must be of equal widths and touching.

Frequency Polygon A line graph, utilized much like a histogram, that gives a visual appreciation of the shape of the frequency distribution. The midpoint of each bar is used to represent the whole interval. Lines are then draw between these midpoints.

The weights of parcels sent on a given day from a post office were, in kg: 2.9, 4.0, 1.6, 3.5, 2.9, 3.4, 3.2, 5.2, 4.6, 3.1, 2.8, 3.7, 4.9, 3.4, 1.3, 2.5, 2.2 Problem 2

Make a Frequency Table and a Histogram for the post office data. Weight Frequency 1  w <2 2  w <3 3  w <4 4  w <5 5  w <6

Results from the post office data.

To Summarize: Discrete Data Frequency Table Stem and Leaf Plot Column Graph Continuous Data Frequency Table Histogram

Homework Exercise 5C, pg 120 – #1, 2 Exercise 5D, pg 123 – #1, 3